A Boston police officer mans a closed off neighborhood as a search for the second of two suspects wanted in the Boston Marathon bombings takes place April 19, 2013 in Watertown, Massachusetts. Police killed one of the suspected Boston marathon bombing suspects in a shootout early today and pursued a chaotic deadly street-to-street manhunt for his accomplice, officials said. AFP PHOTO/Stan HONDA (Photo credit should read STAN HONDA/AFP/Getty Images)

Boston on lockdown while police hunt for bombing suspect [PHOTOS]

Boston police have the entire city of Boston, as well as neighboring suburbs Cambridge, Brookline, Newton and Watertown on lockdown as they continue their manhunt for Dzhokhar Tsarnaev.

Tsarnaev is one of the suspects in the Boston Marathon bombing and is still at large and remains armed and extremely dangerous.

His older brother Tamerlan is dead following a shootout late Thursday that left one Massachusetts Institute of Technology police officer dead after the brothers robbed a gas station and hijacked an SUV in Cambridge.